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Ed in SoDak's Photo

Ed in SoDak

Member Since 22 Mar 2014
OFFLINE Last Active Feb 20 2019 1:40 AM

Topics I've Started

php1800 sidecar disk controller no worky

Thu Mar 29, 2018 12:49 AM

My dad picked this up in the mid-80's. I don't think it worked then and sure doesn't now. Any schematics or common failures in these? The controller chip might be suspect as a common disk controller problem, so why should the sidecar version be any different? It has voltage, but the +5 is pulled down to 4.87 when connected to the circuit and when it is connected and powered, the -5 line goes a bit more negative compared to its disconnected reading. If that's a clue.


This one is serial 1528133 and LTA0381. So early '81. I know how fragile the thin ribbon wires between the boards are, so I'm reluctant to do my usual disassemble and then give it my best baleful stare.


The drive motor spins at powerup, but no light, head movement or anything other than a console error report. To try it, I just moved the outboard drives' 1&2 cable from my PE box to the sidecar and plugged it into the console port.


I don't have a real use for it, but figure it's worth more working, if it's a fairly simple fix, such as locating and installing a new controller chip, assuming it's not unobtainium.


Thanks in advance!



TI History with a bit of drama

Wed Mar 21, 2018 11:44 PM

I've been re-reading (for the umpteenth time) old issues of Micropendium. Back then, it was my (our?) primary news and info source. One by one, old newsletters and sources vanished, but M'Pendium remained till its own bitter end in '99. The internet was taking off and many formerly loyal subscribers had already departed for other pastures to browse upon.


Reading in the 89-91 timeframe, a lot of new stuff was happening. But it wasn't all rosy. Seems to me some people had mighty thin skins and all it took was a seeming small slight that made its way into print might cause an author to drop the TI (only to come back later - or not!), some notable deaths that happened way too young (John Guion and John BIrdwell to mention two) and the on-going saga of when will MDOS get finalized?


In one rather notable issue, April '91, John Koloen reported he had been taken to task ("Apology to a Reader") for accepting "fraudulent" ads from Myarc over their statement in their advertising for the HFDC that it supported streamer tape backup. John's letter to Lou Phillips resulted in a call from Phillips back to Micropendium where Myarc withdrew all support of Micropendium. And that was that. The loss of two full-page ads per month had to hurt, but John didn't kiss up or back down and it probably hurt both concerns, over one single phone call. And the month prior, someone was also raked over the coals online for releasing some MDOS .98h beta version he'd come across, and was just trying to share it.


This many years later, it seems to this reader some folks had thin skins, but maybe their skins had been stretched far enough already. What could John Koloen do, but draw up his chin and continue in true journalistic fashion and try to keep his reporting as fair as he could. It must have been a challenge for him and Laura some months to keep that even keel. There was simply no way to please everyone, but they sure tried their darndest.


Developing for or supporting any Orphan computer was in those days probably as much a labor of love as anything. Seeing (or not seeing) your name in print meant a lot and criticism usually stung a bit. The same might be true now as it was back then, but it doesn't reach the point where somebody takes his foot ball and goes home nearly as often.


But, boy, things sure coulda turned out differently if some of those in-print conflicts could have been worked out more amicably!


While I'm not actively purchasing new stuff for my ol' TI, I'm truly amazed at all the offerings today that have built on those foundations laid long ago. The new mantra of open-source and shared resources has helped in no small way, along with much better tools to work with. And it's easy to see many of the players from back then are still around and active here.


One thing for sure, I don't see those thinly veiled barbs (real or imagined) and reactionary rebuttals being slung about now, like I saw in those old pages. No doubt, as heavily-financed small businesses succumbed to the reality of a dwindling market, it became more than personal to many.


It must have been a stressful time in those years for anyone seriously trying to support the TI (and hopefully also earn a yeoman's wage doing it)!



I need an extraction!

Sun Mar 11, 2018 10:34 AM

I hope somebody here can help. I'm trying to retrieve Harry Willhelm's Kwikfont program from this disk I found at WHT. It seems to be in V9T9 format, but I  haven't figured out how to mount disk images yet so I need the individual files.


I can open and extract from TIFILES disks, but not this type. Can someone lend a hand?


Thanks in advance!



Ribbon cable extender for the Firehose

Sat Mar 10, 2018 2:35 AM

I guess I'm one of the lucky few who has one of these. With all the new add-ons being developed, maybe now someone has found a source for the connectors and could produce this handy item.


Mine is about 36 inches, I haven't measured it in awhile. Long enough to put the firehose down on the floor with only the easily foldable ribbon cable connecting the PEB to the TI. Who needs that huge dongle laying on the desk, preventing the console from moving or breaking contact if it does move.


Those of us with PEBs need this!


PRINT CHR$(14913) prints "A"

Thu Mar 8, 2018 7:46 PM

Just a quirk of the TI99/4A I'm sure, but thought it interesting, though hardly useful. If you redefine A, it will show up at 14913 the same as CHR$(65). I was messing around and discovered the character set is repeated over and over as you increase the character numbers on upwards, till at some point around 32000 it scrambled part of my line of code I had written to enter and display it.


Attempting to redefine char# 14913 or any number other than the usual results in an error. But changing #65 redefines all the repeating A characters wherever they may be, and there's many duplicated character sets as you keep looking.


OK, I'm bored, how else to explain? :)